Question

Describe the research foundations of stimulus equivalence, Why is this important and What are the four types of probe trials in equivalence studies?

Answer 1

Research foundations are the queries,, that is How do organisms come to treat dissimilar events as if they are the same, particularly events that have never been related directly? This question has long fascinated philosophers and psychologists. For philosophers the events of interest were ideas, and processes by which ideas became equivalent took place inside the heads of human organisms. They conceived that ideas (A and B) that had never been associated directly but were each associated with a third idea (C) might come to be associated, such that the three ideas were interchangeable. Several psychologists who became interested in this question saw that a range of events—not just “ideas”—could potentially become equivalent to one another as a result of organism—environment interactions.

Four equivalence test blocks (BC and CB probes, which tested simultaneously for both symmetry and transitivity) were followed by four symmetry (BA and CA probes) test blocks. Three subjects' results documented emergent performances indicative of equivalence classes despite fast-responding requirements that severely limited the time available for mediating vocal or subvocal responses. For these three subjects, mean latencies were slightly shorter in baseline trials than in probes, and shorter on symmetry than on equivalence probes. These differences, however, were usually less than the differences among mean latencies on the different types of trials within the baseline and probed performances.